What the P0847 code means?
The P0847 code is a standard OBD-II trouble code that detects a problem with the transmission fluid pressure "B" circuit. The "B" represents an area of the transmission fluid pressure circuit, rather than an individual component. The vehicle's automatic transmission relies on electronic pressure control solenoids to manage the hydraulic pressure, which is used to help the vehicle shift, and to aid torque converter lockup. The solenoids are controlled by the power train control module (PCM), which uses a host of information (such as engine speed, throttle position, and vehicle speed) to determine the ideal amount of fluid pressure.
What causes the P0847 code?
1. Short to ground in the signal circuit to the TFPS sensor
2. Failed TFPS Sensor / internally shorted
3. Failed PCM
What are the symptoms of the P0847 code?
These may vary from no detectable symptoms at all to disabled shifting function and a failure of the torque converter clutch to engage/disengage. This code may also be accompanied by the PCM placing the transmission in "limp-in" mode. Other symptoms may include harsh shifting, transmission slippage, transmission overheating, decreased fuel efficiency, a stored code, and possibly an illuminated malfunction indicator lamp. Other torque converter clutch, lock up, gear ratio, shift solenoid, or transmission slippage codes often accompany this code.
Common mistakes when diagnosing the P0847 code:
Technicians report that transmission pressure sensor, electronic pressure control solenoid, and system wiring malfunctions are often overlooked and high pressure pumps are frequently replaced in error.
What repairs can fix the P0847 code?
Replacement of electrical components in the transmission system
Replacement or addition of transmission fluid
Fixing of hydraulic blockages in the transmission system
Electronic pressure control solenoid replacement
Electronic pressure regulator replacement